Electronic document publishing often demands more than a stack of paper in an output tray of an office printer. Typically, a plurality of duplex printed sheets are bound into finished documents by a publishing system that prints and finishes books. Publishing systems perform operations such as collating, binding, folding, trimming, stapling, etc. These finishing operations are typically performed on all of the sheets in a book at one time, which generally requires the use of high forces and powerful motors. Consequently, the systems adapted to perform these functions are relatively expensive and often exceed the cost of other desktop or office printers. As such, known publishing systems are not generally well suited for use in low-cost desktop bookmaking.
In order to lower the cost of publishing systems, the forces within the publishing system are typically decreased or minimized. Accordingly, sheet-wise folding systems have developed in which individual sheets are folded and subsequently accumulated rather than folding the entire stack of sheets at one time. However, booklets folded by conventional low-force publishing systems oftentimes do not exhibit crisp fold lines, which contributes to the creation of undesirable pillowing or puckering of the booklet sheets around the spine of the booklet. Since pillowing is generally indicative of a low-quality booklet, a publishing system is desired that includes a folding apparatus that utilizes low magnitude forces and while also decreasing pillowing the bound documents output from the publishing system.